LONDON, June 7 (Reuters) - Middle East tensions, Britain’s election and Donald Trump’s troubles combined to dampen investors’ risk appetite on emerging markets on Wednesday, with currencies suffering and stocks edging lower for a second day.

The decision by several Arab states to cut diplomatic ties with Qatar, accusing it of supporting terrorism, made markets - especially in the region - uneasy

Adding to the frayed nerves were three key events scheduled for Thursday - Britain’s general election, a European Central Bank policy meeting and testimony by former FBI director James Comey which could impact on U.S. President Donald Trump’s economic agenda.

“There are worries about the GCC (Gulf Cooperation Council) and Qatar and how that will play out ... It’s a geopolitical oil story that creates a risk off sentiment,” said Per Hammarlund at SEB.

“In the U.K., people are sitting on the sidelines and waiting to see how this will pan out - if you have an acrimonious Brexit that will hurt the Central and Eastern European countries, and it could hurt the EU too, so it has wider ramifications.”

Markets in the Gulf remained under some pressure after U.S. President Donald Trump supported Saudi Arabia against Qatar.

Qatar’s stock exchange fell 0.3 percent, having tumbled nearly 9 percent over the last two days. Doha’s dollar-denominated debt edged lower across the curve, with some issues trading at their weakest in around 2-1/2 months.

Currencies fared little better, despite a steady dollar.

South Africa’s rand had a soft start to the session after data showed on Tuesday that Africa’s most industrialized nation slipped into recession for the first time in eight years.

The news raised the prospect of further credit rating downgrades and heaped pressure on President Jacob Zuma, who is already facing corruption allegations.

However, the rand recovered most of its losses to trade 0.2 percent weaker after central bank data showed FX reserves grew unexpectedly.

“The downgrade question is definitely one of the factors,” said SEB’s Hammarlund, referring to Moody’s next assessment scheduled for release on Friday.

“But if you look at the rand and emerging markets in general over the longer term, you are still looking at a positive cycle - the worries about the rand will be short lived.”

Russia’s rouble and Mexico’s peso also weakened against the dollar.

In Poland, central bank policy makers are scheduled to conclude their interest rate setting meeting, though analysts expect no change until the third quarter of 2018 given the benign outlook for inflation. Interest rates are at an all-time low of 1.5 percent.